Hi The Toddler,
I think that post #2 here is what you’re looking for :).
I would still rotate the mattress so that the mattress will break in more evenly (and you won’t be assessing the suitability of a mattress that has broken in unevenly which may be misleading) and you should still be able to get a good sense of whether things are working out for you by the end of the 30 days.
Phoenix